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United States Patent | 5,719,494 |
Dettmann ,   et al. | February 17, 1998 |
A sensor assembly for measuring current I.sub.o is disclosed. The sensor assembly includes four magnetoresistive resistors (1, 2, 3, 4) arranged to form a Wheatstone bridge. The bridge is disposed over a U shaped conductor 14. The resistors are arranged so that two resistors (1,2) forming one bridge branch are disposed over one leg of the conductor and the two resistors (3,4) forming the other bridge branch are disposed over the other leg of the conductor. Each resistor is formed out of a number of magnetoresistive strips (1', 2', 3', 4'). The magnetoresistive strips forming the individual bridge branch resistors are interleaved so as to ensure the resistors forming each bridge branch have substantially the same temperature. When current I.sub.o is applied to the conductor, the equal and opposite magnetic fields that develop around the individual bridge branches cause the Wheatstone bridge to produce a signal U.sub.a that is a function of the current.
Inventors: | Dettmann; Fritz (Sinn-Edingen, DE); Loreit; Uwe (Wetzlar, DE); Kunze; Jurgen (Wetzlar, DE); Lust; Karl-Heinz (Lahnau, DE) |
Assignee: | Lust Antriebstechnik GmbH (Lahnau-Waldgirmes, DE) |
Appl. No.: | 543194 |
Filed: | October 13, 1995 |
Oct 15, 1994[DE] | 44 36 876.3 |
Current U.S. Class: | 324/117R; 324/252 |
Intern'l Class: | G01R 033/00; G01R 033/02 |
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